1. Field of the Invention
The present invention relates to equipment used in adjusting and servicing internal combustion engines such as automobile engines, and more particularly to an arrangement for indicating when a piston of an internal combustion engine has reached the top-dead-center position.
2. History of the Prior Art
When tuning an automotive or similar internal combustion engine it is often desirable that the distributor be removed from the engine for cleaning and servicing as well as easier installation of new points. However, there is a reluctance on the part of many mechanics, both professional and amateur, to remove the distributor from the engine. This stems from the fact that if the engine is rotated with the distributor removed, it is often difficult for the mechanic to determine the top-dead-center position of one of the engine pistons upon reinstallation of the distributor so that the engine may thereafter be started and more precise adjusting and tuning accomplished.
The conventional technique for attempting to determine the top-dead-center position of a piston upon reinstalling a removed distributor requires two persons to accomplish and is haphazard at best. One person places his finger or thumb over the sparkplug hole of a convenient reference piston such as the number one piston. The second person climbs inside the auto and repeatedly turns on the ignition for short intervals to rotate the engine in increments. When the piston reaches top-dead-center during the compression stroke, pressurized air tends to force the thumb or finger of the first person away from the sparkplug hole. Aside from being crude and somewhat haphazard, this technique is limited to a two man operation because of the virtual impossibility for one person to hold their finger over the sparkplug hole and at the same time turn on the ignition.
Accordingly, it is an object of the invention to provide a detector for indicating rather precisely when a piston has reached the top-dead-center position.
It is a further object of the invention to provide a piston top-dead-center detector utilizing a flashing lamp or other warning device which is detectable at a location removed from the engine compartment such as from the inside of the vehicle.
It is a still further object of the invention to provide a piston top-dead-center detector useful in a variety of different operations such as ascertaining the timing of the engine as well as aiding in the reinstallation of the engine distributor.